Process for heat treating lengths of textile materials



Sept. 1968 c. A. MEIER-WINDHORST 3,401,412

PROCESS FOR HEAT TREATING LENGTHS OF TEXTILE MATERIALS Filed Feb. 4, 1966 Fig. I

77 Fig.2

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ATTORNEYS United States Patent 3,401,412 PROCESS FOR HEAT TREATING LENGTHS OF TEXTILE MATERIALS Christian August Meier-Windhorst, Hamburg, Germany,

asslgnor to Artos Dr. Ing. Meier-Windhorst K.G., Hamburg, Germany, a corporation of Germany Filed Feb. 4, 1966, Ser. No. 525,085

Claims priority, application Germany, Feb. 10, 1965,

6 Claims. oi. 8149.3)

ABSTRACT OF THE DISCLOSURE Moving lengths of textile or textile-like materials which are subjected to a heat treatment and impregnation are additionally treated by a regulated specific steam-air-mixture for the purpose of maintaining uniform predetermined treating conditions, the additional treatment taking place in a zone located in front of the main treating chamber by the steam-air mixture which flows in a direction opposite to that of the movement of the material.

This invention relates to a process for continuously heat treating lengths of textile or textile-like materials, particularly for the purpose of providing certain conditions in the materials.

Experience has shown that it is of utmost importance for all variations of heat treatments used in the textile industry to be able to employ reliably operating heating systems capable of being reproduced at will in order to be able to produce predetermined and continuously uniform conditions in the treated goods. This is not possible in many processes now in use, for example, in bleaching or dyeing.

In the case of so-called pad-roll bleaching the length of material is heated solely by a supply of steam to the pad-roll storage chamber, the material being somewhat freely guided during its introduction into the chamber. In the course of so-called pad-roll dyeing and pad-steam dyeing the heating is generally carried out also by supplying pure steam or in special cases by an uncontrollable superposed radiation heating and condensation heating at the entry of the material into the treating chamber while an additional supply of steam is provided in the storage chamber. In all these processes when operating at temperatures below 100 C. the supply of steam is regulated in accordance with the wet bulb thermometer. Since at temperatures below 100 C. a certain proportion of air must be always present in the medium filling the storage chamber and since this air usually penetrates into the chamber from outside along with the material in a manner which cannot be controlled, it is not possible to provide reliably and precisely predetermined treating conditions and, above all, it is not possible to assure their uniform distribution, so that the heating of the material to a certain predetermined temperature actually can not be reproduced. A further lack of certainty results from the fact that the required minimum length of the material freely guided in the pad-roll chamber can be determined only empirically.

A substantial improvement in the process of heating wet-impregnated lengths of material with a reproducible setting of a predetermined temperature at or in the material, has been attained by introducing controlled steamair mixtures into the treating chamber and providing a counter flow of this steam-air mixture to the direction of movement of the material at the zone of entry of the material. Completely uniform and reproducible treating conditions can be also attained by a directed flushing through the storage chamber and a regulated guiding in Patented Sept. 17, 1968 lice counter-flow through the entire storage and guided space for the length of material being treated.

A further improvement in certain treating processes, particularly for the dyeing, was attained by additionally sub ecting the material in a special heating zone to a combmed steam-condensation heating and condensation-free heating, preferably radiation heating which follow each other and are carefully regulated relatively to each other. However, this special type of increased heating of the material requires greater expenses for the installation and operation.

It was determined experimentally that heating outputs of a heating phase with pure counter current guiding of steam-air mixtures without any additional heating, are less than could have been expected, particularly when the steam content is low, i.e. at desired low treating temperatures, such as for example, C. It was found that the reason for that is that after a short while substantial air concentrations are developed at the outer surface of the material being heated due to the condensation of steam in the boundary layer which takes place in case of pure condensation heating; they do not permit heating to a higher temperature than the lower saturation temperature at partial pressure corresponding to the higher content of air. It is therefore necessary to provide special measures for the purpose of adequately heating the material.

An object of the present invention is to eliminate these prior art drawbacks.

Other objects will become apparent in the course of the following specification.

In the accomplishment of the objectives of the present invention it was found desirable to provide adequate heating of the material by subjecting a length of material impregnated with a treating substance prior to its actual entry into a treating or storage chamber to a treatment in a separate heating zone or in the area of entry of the material into the chamber, a predetermined steam-air mixture being introduced into said chamber in such manner that a uniform distribution of the steam-air mixture throughout the entire space is assured; said treatment is preferably carried out by the steam-air mixture flowing out of the storage chamber in a direction opposite to that of the movement of the material and takes place in such manner that there are no substantial changes in the conditions of the steam-air mixture at the boundary layers of the material being treated, particularly as far as a substantial increase of the proportion of air is concerned.

The boundary layer is torn open by a supply of the steam-air mixture to the material in the heating zone, namely, by blowing the steam-air mixture which is preferably conducted in a closed path, directly upon the material. Steam can be added to the circulating steam-air mixture to compensate for steam losses in the mixture caused by condensation heating. When the steam-air mixture flows in counter-current in the heating zone, steam replacing that amount of steam which was condensed out of the steam-air mixture is applied directly at various locations to the material in order to tear open the boundary layer. The supply of steam to the material should take place in different amounts in different sections of the heating zone, namely, the amount of steam supplied in a certain section should be precisely that which was lost and has to be replaced. I

The apparatus for carrying out the process of the pres ent invention comprises a pad-roll chamber or a transport ing and storage chamber, or a J-box; these chambers serve as a treating chamber and are combined with a heating zone located at the inlet of the material. The heating zone can be provided with upper and lower rollers for transporting the material, steam supplying pipes being located between the loops of the material. However, the heating zone can contain a casing carrying blow nozzles which blow the steam-air mixture directly upon the material. It was found advisable to provide a sluice device at the entry of the material into the heating zone and to arrange a water lock at the exit of the material from the treating chamber. If it is not possible to use Water, arrangements can be made for the material to leave the treating chamber through a slit having a high air fiow resistance, namely, through a very narrow slit or a labyrinth-like slit.

The invention will appear more clearly from the following detailed description when taken in connection with the accompanying drawing showing by way of example only, preferred embodimets of the inventive idea.

In the drawing:

FIG. 1 is a diagrammatic sectional view of an apparatus of the present invention comprising a heating zone constructed as a transporting and storing chamber and connected with a pad-roll storing chamber.

FIGURE 2 is a diagrammatic sectional view of a different embodiment wherein the heating zone is shaped as a nozzle-carrying casing connected with a storing chamber which also constitutes a transporting chamber.

Similar parts are indicated with the same numerals in the drawings.

Both embodiments of FIGS. 1 and 2 pertain to a heat treating apparatus having a heating zone connected with a storing chamber. The material 20 passes through the apparatus as indicated, while arrows show the directions of flow of the steam-air mixture.

The apparatus shown in FIG. 1 includes a heating zone 13 located in front of a pad-roll chamber 10 and constructed as a combined transporting and storing chamber. A sluice 14 is located in front of the heating zone 13 in order to effectively prevent the penetration of atmospheric air into the heating zone.

The steam-air mixture is preferably introduced into the chamber 10 at the bottom of the chamber and then is guided through the apparatus in counter-current to the direction of movement of the material. Steam is introduced through any suitable steam conduit 26 which carries a manually operated valve 25 constituting a pressure regulating device for setting the desired operational pressure of the steam. Steam flows into an injector 24 wherein the steam-air mixture is formed. Steam sucks into the injector 24 a predetermined amount of air regulated by a throttle valve 23 which can be also set manually. The steam-air mixture then flows into the chamber 10.

The actual volume ratio of steam to air in the mixture is determined by the real treating temperature and thus by the temperature of the wet bulb thermometer. The volume of the steam-air mixture actually introduced into the apparatus depends upon the dimensions of the chamber, the construction of the sluice and the desired output. It is also possible to introduce a constant steam-air mixture into the chamber which will have a somewhat lower temperature of the web bulb thermometer. The required temperature of the wet bulb thermometer is then automatically regulated by supplying an additional amount of pure steam through a valve 22 which by-passes the air injector 24 and connects the steam conduit 26 directly with the chamber 10. The valve 22 is operated by a measuring device 27 which is located in the chamber 10 preferably in the section wherein the material is being introduced into the chamber. A guide plate 21 is located in the chamber 10 close to the entry of the steam-air mixture so as to protect the material from a direct impact of the mixture. The guide plate 21 serves at the same time to provide a circulation for the steam-air mixture so as to assure complete uniformity of the mixture in the chamber.

The steam-air mixture leaves the pad-roll chamber 10 through a throttle 19, reaches the heating zone 13 and flows through the heating zone in a direction opposite to the movement of the material, finally flowing outwardly through the sluice 14. Special blow pipes 18 are located in the heating zone 13 which eject pure steam upon the material 20 to make certain that the material is adequately heated. It is advantageous to provide these blow pipes with separate regulating means (not shown), so as to make possible a regulated supply of steam to the material. Then it will be possible to provide the precisely required amount of steam in the various sections of the heating zone 13.

The operation of the apparatus is apparent from the above description. The length of material 20 enters into the heating zone 13 through the sluice 14 and passes betwen upper and lower rollers 15 while being subjected to the action of steam blown through the pipes 18 and the action of the steam-air mixture regulated by valves 22 and 23 and flowing first through the chamber 10 and then through the heating zone 13. The material passes from the heating zone 13 through the throttle 19 and is wound upon a large roller in the pad-roll chamber 10.

The apparatus shown in FIG. 2 includes a heating zone 13 located in front of a treating chamber 11 which is constructed as a combined transporting and storing chamber. The steam-air mixture is introduced through the bottom of the chamber 11; it is supplied and regulated in the same manner as that which has been described already and illustrated in FIG. 1. In this construction the material 20 leaves the chamber 11 through a water-filled container 28 which effectively prevents any penetration of atmosphen'c air into the chamber. In this construction the material is heated by the use of a nozzle casing 17 located in the heating zone 13. A steam conduit 12 which supplies steam into the circulating steam-air mixture is used to compensate for any steam which may have been lost by condensation.

The operation of this apparatus is also apparent from the above description. The length of material 20 passes through the heating zone 13 and between upper and lower rollers in the chamber 11, leaving the chamber 11 through the water-filled container 28.

.It is apparent that the examples described above have been given solely by way of illustration and not by way of limitation and that they are subject to many variations and modifications within the scope of the present invention. All such variations and modifications are to be included within the scope of the present invention.

What is claimed is:

1. A process for setting a predetermined treating temperature and securing a predetermined treatment condition in a textile or textile-like length of material subjected to a continuous heat treatment and impregnated with a treating substance, said process comprising the steps of introducing into a treating space a specific steamair mixture, uniformly distributing said specific steamair mixture throughout said entire space, causing said steam-air mixture to flow into a heating zone, moving said length of material first through said heating zone and then into said treating space in a direction opposite to that of said fiow and in treating engagement with said steam-air mixture while regulating said steam-air mixture to prevent any substantial changes, particularly any substantial increase of air, in said steam-air mixture at the boundary layers of said material.

2. A process in accordance with claim 1, wherein said heating zone constitutes an inlet area for the entry of said material into said treating space.

3. A process in accordance with claim 1, further comprising supplying steam to dilferent portions of the material during its passage through said heating zone to substitute for steam condensed from said steam-air mixture.

4. A process in accordance with claim 1, further comprising supplying different amounts of steam to diiferent 4 5 portions of the material during its passage through said heating zone to substitute for steam condensed from said steam-air mixture.

5. A process in accordance with claim 1, further comprising blowing a steam-air mixture directly upon said length of material while it is moving through said heat ing zone and adding steam to the last-mentioned steamair mixture to compensate for losses resulting from condensation.

6. A process in accordance with claim 5, wherein the last-mentioned steam-air mixture flows along a circular path in said heating zone.

References Cited UNITED STATES PATENTS 1,807,580 6/1931 Allsop 68--5.4 1,992,753 2/1935 Karlson et al 68-5 X 2,346,186 4/1944 Poesl 8-149.3 X

FOREIGN PATENTS 6,724 1907 Great Britain. 457,952 12/ 1936 Great Brita-in.

WILLIAM I. PRICE, Primary Examiner.

IRVING BUNEVICH, Examiner. 

